US6820714B2 - Hydraulically supported steering system - Google Patents

Hydraulically supported steering system Download PDF

Info

Publication number
US6820714B2
US6820714B2 US10/082,662 US8266202A US6820714B2 US 6820714 B2 US6820714 B2 US 6820714B2 US 8266202 A US8266202 A US 8266202A US 6820714 B2 US6820714 B2 US 6820714B2
Authority
US
United States
Prior art keywords
flow
throttle mechanism
hydraulic
cylinder
steering system
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related, expires
Application number
US10/082,662
Other languages
English (en)
Other versions
US20020148670A1 (en
Inventor
Armin Schymczyk
Dirk Sickert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ford Global Technologies LLC
Original Assignee
Visteon Global Technologies Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Visteon Global Technologies Inc filed Critical Visteon Global Technologies Inc
Assigned to VISTEON GLOBAL TECHNOLOGIES, INC. reassignment VISTEON GLOBAL TECHNOLOGIES, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SCHYMEZYK, ARMIN, SICKERT, DIRK
Publication of US20020148670A1 publication Critical patent/US20020148670A1/en
Application granted granted Critical
Publication of US6820714B2 publication Critical patent/US6820714B2/en
Assigned to AUTOMOTIVE COMPONENTS HOLDINGS, LLC reassignment AUTOMOTIVE COMPONENTS HOLDINGS, LLC ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: VISTEON GLOBAL TECHNOLOGIES, INC.
Assigned to FORD MOTOR COMPANY reassignment FORD MOTOR COMPANY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: AUTOMOTIVE COMPONENTS HOLDINGS, LLC
Assigned to FORD GLOBAL TECHNOLOGIES, LLC reassignment FORD GLOBAL TECHNOLOGIES, LLC ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FORD MOTOR COMPANY
Adjusted expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/062—Details, component parts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D7/00—Steering linkage; Stub axles or their mountings
    • B62D7/22—Arrangements for reducing or eliminating reaction, e.g. vibration, from parts, e.g. wheels, of the steering system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F16F9/34—Special valve constructions; Shape or construction of throttling passages
    • F16F9/3415—Special valve constructions; Shape or construction of throttling passages characterised by comprising plastics, elastomeric or porous elements

Definitions

  • the invention relates to a hydraulically supported steering system with a steering gear that is driven by a hydraulic piston/cylinder unit.
  • Hydraulically supported steering systems have been known for a long time. It is moreover well known that pronounced smooth running of the steering gear can positively effect a vehicle's handling characteristics. However, smooth-running steering gears make the entire steering system susceptible to oscillations. Therefore, it is necessary to use steering dampers to effectively combat the oscillations in the steering system.
  • An example of a hydraulically operated steering stabilizer is illustrated in U.S. Pat. No. 4,467,884.
  • undesired noise can develop in hydraulically supported steering systems (“water line knocking”) when erratic pressure changes appear in the hydraulic system and pressure peaks reach the system's return line. This can be caused for example, by external disturbances that act upon the steering wheel during driving.
  • Hydrodynamic damping elements (“throttles” or “compensating volumes”) are often used in hydraulically-supported steering systems for damping the undesired noise.
  • DE 28 38 151 A1 discloses a hydraulic piston/cylinder unit that can be used both as a steering system's hydraulic support as well as a steering damper. Additionally, DE 40 29 156 A1 discloses that in order to suppress undesired oscillation or erratic pressure changes in a hydraulically supported steering system in which the piston/cylinder unit also acts as a steering damper, damping valves that are only operative in the supply direction to the cylinder subchambers can be advantageously installed into the hydraulic lines of the piston/cylinder unit's cylinder subchambers.
  • a speed-dependent steering system is disclosed in DE 28 38 151 A1.
  • This disclosure proposes a steering system comprising of a piston/cylinder unit that only operates as a steering aid at low vehicle speeds and only serves as a steering damper at higher speeds. For this, the vehicle speed is analyzed by electronic means and the piston/cylinder unit is only pressurized when necessary.
  • this device as disclosed in the patent, has a number of drawbacks, the device firstly requires detection of the vehicle speed and electrical or electronic evaluation of this information, and secondly requires an electrically controlled power-assisted device for pneumatic control. Both factors increase the cost, and the steering system's high complexity makes it susceptible to problems or failure, making it more difficult to use the system in the smaller sized cars.
  • EP 1 013 535 A1 discloses a hydraulically supported steering system, which works with variable throttle valves in the hydraulic supply lines to the cylinder subchambers, and whose flow resistance is determined from pressure difference between the pressure produced by the hydraulic pump and the pressure in the return line to the hydraulic fluid reservoir.
  • the hydraulic pump is lock-synchronized with the combustion engine that drives the vehicle. Since the pressure generated by the hydraulic pump is a function of engine speed, the characteristic curve of the hydraulically supported steering system is a function of vehicle speed.
  • the variable throttle valve that is required is mechanically expensive and requires extra hydraulic control lines, which make retrofitting difficult, particularly in existing old cars.
  • lock-synchronization of the combustion engine and hydraulic pump cannot be assumed in all cases, so the advantage of a steering system whose characteristic curve is a function of speed can't be realized in all vehicles.
  • DE 196 51 500 C1 discloses a damping valve arrangement for a hydraulic steering system.
  • a check valve and a throttle valve are combined within one component, whereby the throttle valve's flow resistance adapts itself to the temperature-dependent viscosity of the hydraulic fluid. This is realized by using temperature-sensitive mechanical setting elements that vary the opening of a bypass path realized through throttle valve as a function of temperature.
  • an adaptation of the throttle valve's damping action to the respective driving situation cannot be inferred from the disclosure.
  • the damping characteristics of the unit automatically adapt themselves to the motor vehicle's driving situation at hand.
  • a steering system comprises a piston/cylinder unit that supports the steering gear's movement.
  • the piston/cylinder unit comprises a piston, which is axially displaced within a working cylinder and divides the cylinder into two cylinder chambers.
  • Each cylinder chamber is connected to a separate hydraulic line that serves both as pressure supply line and as a return line. Both hydraulic lines are also connected to a servo valve actuated by steering movements of the vehicle.
  • a self-regulating throttle mechanism which features a variable flow resistance in at least one flow direction, is arranged in at least one hydraulic line.
  • the flow of hydraulic fluid through the throttle mechanism determines the flow resistance of the self-regulating throttle mechanism in this flow direction. If there is a lower flow of hydraulic fluid through the throttle mechanism, then a higher flow resistance will arise and lead to an effective damping of oscillations and erratic pressure changes in the hydraulic system.
  • a lower flow of hydraulic fluid will occur, when the driver undertakes small driving angle corrections at higher vehicle speeds. There will consequently be less hydraulic support of the steering system at higher vehicle speeds, this will have a positive effect on the vehicle's handling characteristics, especially on its driving stability. Moreover, disturbances on the vehicle's wheels will result in motions of the steering gear, motions that the piston/cylinder unit acting as steering damper will dampen, especially when the steering column hasn't been actuated. Without effective damping of the steering gear, these disturbances will transmit itself to the steering column in the form of a “knocking” that is uncomfortable to the driver.
  • piston/cylinder unit acts as a steering damper, then only trivial compensating motions of the piston will occur within the working cylinder and they will be accompanied by only a small flow of hydraulic fluid into the cylinder chambers or out of the cylinder chambers, respectively.
  • the throttle mechanism is designed in such a manner that a lower flow resistance will occur through the throttle mechanism under the above described conditions. This will ensure that full hydraulic support will be available, even for strong steering movements.
  • An analogous mode of operating the throttle mechanism occurs when the throttle mechanism's hydrodynamic damping with the characteristic curve described above adapts itself to the speed of the pressure change in the hydraulic line between servo valve and throttle mechanism or to the size of the dynamic pressure difference occurring in front of or behind the throttle mechanism, rather than reacting to the flow of hydraulic fluid through the throttle mechanism.
  • the throttle mechanism only demonstrates one flow path. This greatly reduces the structural and production engineering cost of the throttle mechanism in comparison to the multipath damping valves known.
  • the self-regulating throttle mechanism demonstrates an asymmetrical flow-resistance characteristic curve in relation to the hydraulic fluid's flow direction, namely a “blocked direction” and a “flow-through direction”. It is particularly advantageous for this type of self-regulating throttle mechanisms to be arranged in both hydraulic lines. In respect to the pressure intake in the cylinder chambers, the throttle mechanisms are each advantageously arranged in the flow-through direction. Such a fitting arrangement makes it possible to quickly fill the particular cylinder chamber that is contributing to a force on the steering wheel in support of the steering motion, so that the full hydraulic supporting force is available, even for rapid steering motions. The high damping required for a steering damper occurs in the opposite flow direction.
  • Throttle mechanisms that demonstrate a high flow resistance in the blocked direction up to the hydraulic fluid's maximum flow, in other words throttle mechanisms that realize high internal damping, can be used as an auxiliary comfort and safety feature. It is of particular advantage for the flow resistance in this blocked direction to remain essentially constant, independent of the flow of hydraulic fluid, until a threshold is reached. When the maximum flow is exceeded, however, the throttle mechanism “opens” into a “safety state;” i.e., its flow resistance advantageously drops jump-like to a low value to realize the hydraulic system's full supporting action.
  • the self-regulating throttle mechanism demonstrates, in the flow direction, a flow-through state with little flow resistance and a damping state with elevated flow resistance.
  • FIG. 1 is a schematic illustration of a hydraulically supported steering system
  • FIG. 2 is a first embodiment of a throttle mechanism according to the invention
  • FIG. 3 is a cross-sectional view through the throttle mechanism along the line A—A in FIG. 2;
  • FIG. 4 is a cross-sectional view through the throttle mechanism wherein its flow resistance flow is reduced by a hydraulic fluid
  • FIG. 5 is a cross-sectional view of a second embodiment of the throttle mechanism along line A—A in FIG. 2;
  • FIG. 6 is a cross-sectional view of a third embodiment of the throttle element along line A—A in FIG. 2;
  • FIG. 7 is a representation of the fourth embodiment of the throttle mechanism with stayed diaphragm segments.
  • FIG. 8 is a cross-sectional view of the throttle mechanism depicted in FIG. 7 along line B—B.
  • FIG. 1 The design of a hydraulically supported steering system is shown schematically in FIG. 1 .
  • the steering column 3 transmits the driver's steering movements on a steering wheel 2 to a pinion 16 .
  • the pinion 16 engages teeth that are designed on the steering rack 14 .
  • Rotation of the steering wheel 2 consequently results in a translation movement of the steering rack 14 .
  • This translation movement which tie rods 15 transmit to the vehicle's wheels 1 .
  • This movement changes the angle of incidence of the wheels 1 to the vehicle's longitudinal axis.
  • a piston/cylinder unit consists of a piston 23 that moves within a working cylinder 24 and divides the cylinder 24 into two cylinder chambers 25 , 26 .
  • the piston 23 hydraulically supports the translation movement of the tie rod 15 .
  • Hydraulic lines 10 , 11 are adapted to pressurize both cylinder chambers 25 , 26 with a hydraulic fluid.
  • the hydraulic lines 10 , 11 are connected to a servo valve 5 , whose setting is influenced by a steering angle sensor 4 .
  • the steering angle sensor 4 is arranged on steering column 3 and senses the driver's steering movements.
  • a hydraulic pressure line 9 connects one side of the servo valve 5 to a power-steering pump 7 that delivers the accumulated hydraulic fluid into a return reservoir 6 .
  • a pressure accumulator reservoir (not shown here), which collects the pressurized hydraulic fluid, can also be arranged between power-steering pump 7 and servo valve 5 .
  • a hydraulic line 8 connects the other side of servo valve 5 to the return reservoir 6 .
  • each of the at least one hydraulic lines 10 , 11 is able to serve as both a pressure supply line and as a pressure return line.
  • the invention does not require a hydraulic line 10 , 11 to serve as both a pressure supply line and as a return line.
  • servo valve 5 connects one of the cylinder chambers 25 , 26 to hydraulic pressure line 9 and one of the cylinder chambers 25 , 26 (e.g., 26 ) to hydraulic line 8 .
  • the cylinder chamber 25 may be connected to hydraulic line 9 , and the cylinder chamber 26 to hydraulic line 8 .
  • This ensures that the flow of pressurized hydraulic fluid flows from cylinder chamber 26 and into cylinder chamber 25 .
  • the flow of the hydraulic fluid from one chamber to another results in a force on steering rack 14 , which operates in a direction from the cylinder chamber 25 toward the cylinder chamber 26 and supports the movement of the wheels 1 .
  • the flow cross section of the servo valve 5 is a function of the turning rate of the steering column 3 in such a way that a high flow of hydraulic fluid will occur into or out of cylinder chambers 25 , 26 , respectively, when there are rapid steering motions.
  • the throttle mechanisms 12 , 13 are disposed in the hydraulic lines 10 , 11 so that the disturbances operating on the wheels 1 during driving, will not lead to oscillations or erratic pressure jumps in the hydraulic system.
  • the use of only one throttle mechanism 12 can be sufficient in principle, but better results can be attained with at least one throttle mechanism per hydraulic line 10 , 11 .
  • the self-regulating throttle mechanism 12 , 13 is made of a circular diaphragm 18 that resists the hydraulic fluid and is arranged perpendicularly to the flow direction in the hydraulic lines 10 , 11 .
  • diaphragm 18 is fastened into a circular mounting 17 .
  • diaphragm 18 is also divided into several segments 21 , which are arranged around a common center Z. Cut surfaces 22 (shown in FIG. 3 ), which run vertically, cut the circular diaphragm 18 into the four segments 21 .
  • the cut surfaces 22 do not extend as far as the external perimeter of diaphragm 18 , so that the diaphragm 18 remains joined together in one piece.
  • the longitudinal axis of the central boring 20 constructed within diaphragm 18 , extends through the center Z, whereby the longitudinal axis is oriented in the flow direction.
  • the diaphragm preferably consists of a natural or synthetic rubber, such as NBR (“neoprene butylene rubber”), HNBR or a poly-styrene-butadiene-copolymer that resists the hydraulic fluid and is resistant to the temperature differences that occur during operation.
  • NBR non-prene butylene rubber
  • HNBR poly-styrene-butadiene-copolymer
  • many of the elastomeric materials used in the automotive industry as sealing materials for hydraulic systems can be used.
  • the use of permanently elastic metallic materials can be advantageous for diaphragm 18 .
  • the mounting 17 consists for example, of a metal like aluminum or a plastic, such as a thermoset plastic that likewise resists the hydraulic fluid and is resistant to the temperature gradient or differences.
  • the central boring 20 ensures that a finite flow resistance will occur, even when the flow of hydraulic fluid through the throttle mechanism 12 , 13 is disappearing. It will also ensure that the servo valve 5 will not completely shut off the cylinder chambers 25 , 26 . This has a positive effect on the piston/cylinder unit as pure steering damper. However, a central boring 20 is not absolutely required.
  • Diaphragm 18 is designed as a disc-shaped. Typical dimensions of the mounting are an outside diameter of about 10 millimeters and thin width of 8 millimeters. Diaphragm 18 , which consists of NBR, demonstrates a thickness of several millimeters, preferably 1 to 2 millimeters depending on the flexibility of the material used for diaphragm 18 .
  • the diameter of the central boring 20 typically amounts to less than 1 millimeter. The diameter of central boring 20 determines the inside diameter ID of the flow path through the throttle mechanism in the illustrated state of rest.
  • the diameter of the central region 19 of diaphragm 18 which is divided into segments 21 , equals several millimeters, preferably about 5 millimeters. A division of diaphragm 18 into more or less than four segments 21 is of course possible and can be advantageous, depending on the application.
  • diaphragm 18 The deformation of diaphragm 18 that results from a flow of hydraulic fluid through throttle mechanism 12 , 13 and the associated widening of the inside diameter ID of the flow path through throttle mechanism 12 , 13 is shown in FIG. 4 .
  • diaphragm 18 deforms itself elastically within its segmented central region 19 , so that the inside diameter ID of the path of flow through throttle mechanism 12 , 13 enlarges. Additionally, a flow of hydraulic fluid can occur through the adjacent segments 21 . If the flow of hydraulic fluid increases in the indicated direction R, the widening of the inside diameter ID will correspondingly increase. If the flow drops again, the diaphragm 18 will relax back into its initial state.
  • Diaphragm 18 is built largely symmetrical in the shown example, so that a comparable characteristic curve of the flow resistance of the throttle mechanism 12 , 13 exists in the two possible flow directions.
  • FIG. 5 represents a second embodiment of the throttle mechanism along the line A—A on FIG. 2 .
  • the basic geometry and all dimensions are comparable with those of the first embodiment.
  • the diaphragm 18 demonstrates conical indentations on its two circular surfaces that reduce the diaphragm's thickness toward their center, which coincides with the common center Z of the segments 21 . From this, it results that the thickness of segments 21 steadily increases outwardly from the center Z, whereby the inside diameter ID of the flow path through throttle mechanism 12 , 13 increases more strongly when the flow of hydraulic fluid is low than when the flow is high. Since the hydrodynamic damping action of throttle mechanism 12 , 13 is mainly determined by the cross section of the flow path, which itself is a quadratic function of the inside diameter ID, a change of damping action that is basically proportional to the change of flow can be accomplished.
  • FIG. 6 shows a third embodiment of the throttle mechanism along the line A—A in FIG. 2 .
  • Diaphragm 18 is not designed disc-shaped in this case, but demonstrates the shape of the envelope of a cone, wherein the tip of the cone lies on a line that is oriented in the flow direction and has center Z, that is, the cone's axis is aligned co-linearly with the flow direction in the hydraulic line 10 , 11 .
  • cut surfaces 22 standing vertical to the plane of mounting 17 divide the diaphragm 18 into four segments 21 .
  • the envelope's wall thickness decreases toward the cone's tip, whereby a damping characteristic comparable to that of the second example is achieved.
  • the conical design of diaphragm 18 achieves an asymmetrical damping behavior of throttle mechanism 12 , 13 in relation to the hydraulic fluid's flow direction.
  • the flow resistance/flow characteristic curve of throttle mechanism 12 , 13 in the flow direction indicated by the arrow R in FIG. 6 basically corresponds to that of the second embodiment.
  • an increase of flow through the throttle mechanism in the opposite flow direction does not lead to an enlargement of the flow path's inside diameter ID, because the segments 21 can't “bend apart” due to their mutual support.
  • the inside diameter ID remains practically constant up to maximum flow; i.e., throttle mechanism 12 , 13 realizes a high flow resistance that is basically independent of the flow and whose size, in practice, is determined only by the diameter of the central boring 20 .
  • the third embodiment accordingly realizes a self-regulating throttle mechanism, which demonstrates flow resistance in a first flow direction called the “flow-through direction” that continuously declines as the hydraulic fluid increases, that is, a “flow-through state” is present here.
  • the self-regulating throttle mechanism demonstrates a “blocking state” with quasi-constant high flow resistance.
  • the throttle mechanism 12 , 13 switches into a “safety state” with small flow resistance when a maximum flow is exceeded. This case realizes all functions with a single flow path and the simplest mechanical design.
  • the throttle mechanisms 12 , 13 depicted in FIG. 6 are installed into the two hydraulic lines 10 , 11 , whereby in the supply direction they are oriented in the flow-through direction to their respective cylinder chamber 25 , 26 .
  • This ensures that a low flow resistance in the supply and permits a high regulating speeds for the piston/cylinder unit.
  • a mechanical support of segments 21 which limits the regulating flow cross section/flow resistance at high flows of hydraulic fluid, can be of advantage.
  • a cage is connected to the mounting 17 and forms bearing surfaces for the maximally deflected segments 21 , and in this manner mechanically prevents further enlargement of the flow path's inside diameter ID.
  • FIG. 7 shows an alternative embodiment of cut surfaces 22 .
  • the cut surfaces 22 gives the diaphragm 18 a higher resistance to premature widening of the flow path's inside diameter ID at higher flows of hydraulic fluid.
  • the cut surfaces 22 are not perpendicular to the diaphragm's plane, but run completely through the center Z at an angle relative to the diaphragm's plane. The angle is preferably in the range of 30° and 60°. This accomplishes that segments 21 mutually support each other in the flow direction, preventing the segments 21 from “bending open” prematurely or too easily.
  • FIG. 8 shows the cut surfaces along the line B—B, of FIG. 7 .
  • the throttle mechanisms as shown in the Figs. have an advantage that the failure of one of the throttle mechanisms 12 or 13 will not cause the hydraulic system to fail. If diaphragm 18 is damaged so that it can no longer relax in its state of equilibrium, this will result in only a minutely reduced internal damping of the steering system.
  • the reduced internal damping of the steering system is largely independent of the vehicle's driving condition and will not affect driving safety.
  • the throttle mechanisms 12 , 13 can also be installed in hydraulic pressure line 9 to dampen undesired pressure bursts. This will suppress the known “water line effect” associated with noise generation.
  • throttle mechanisms that demonstrate the flow resistance/flow characteristic curve.
  • a throttle mechanism based on a circular screen, wherein a ball that is mounted in the mechanism's center.
  • the ball is preferably spring-loaded against a restoring force in and opposite the flow direction and is deflected from its rest state by the flow of hydraulic fluid.
  • the screen's central boring is filled up depending on the diversion thereby varying the flow cross section through the screen.
  • throttle mechanisms 12 , 13 possessing the required characteristics, can be used.
  • Utilization of several throttle mechanisms 12 , 13 in one hydraulic line 10 , 11 can be advantageous for very easy moving steering gears in order to realize the required hydraulic damping characteristics.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • General Engineering & Computer Science (AREA)
  • Power Steering Mechanism (AREA)
  • Fluid-Damping Devices (AREA)
US10/082,662 2001-02-23 2002-02-25 Hydraulically supported steering system Expired - Fee Related US6820714B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE01104338 2001-02-23
EP01104338A EP1234748B1 (fr) 2001-02-23 2001-02-23 Soupape d'amortissement pour dispositif de direction assistée
DE01104338.7 2001-02-23

Publications (2)

Publication Number Publication Date
US20020148670A1 US20020148670A1 (en) 2002-10-17
US6820714B2 true US6820714B2 (en) 2004-11-23

Family

ID=8176571

Family Applications (1)

Application Number Title Priority Date Filing Date
US10/082,662 Expired - Fee Related US6820714B2 (en) 2001-02-23 2002-02-25 Hydraulically supported steering system

Country Status (4)

Country Link
US (1) US6820714B2 (fr)
EP (1) EP1234748B1 (fr)
JP (1) JP3689055B2 (fr)
DE (1) DE50100952D1 (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050133294A1 (en) * 2003-12-23 2005-06-23 Hyo Chun Co., Ltd. Industrial vehicle
US20050252667A1 (en) * 2004-05-05 2005-11-17 James Berkeley Trap rake steering travel limiter
AU2007100088B4 (en) * 2006-02-06 2007-03-08 Truck Whisperer Limited Method and apparatus for enhancing car performance
US20070193641A1 (en) * 2005-12-22 2007-08-23 John Dooley Power steering system frequency suppressor
US20090173565A1 (en) * 2005-12-19 2009-07-09 Kenneth John Dennis Method and apparatus for enhancing vehicle performance
US20090198411A1 (en) * 2008-02-06 2009-08-06 Kohls Mark T Electronic steering damper systems and vehicles including same
US20110302976A1 (en) * 2008-12-05 2011-12-15 Georg Keintzel Method and apparatus for semiactive reduction of pressure oscillations in a hydraulic system
US20120000543A1 (en) * 2008-12-05 2012-01-05 Georg Keintzel Method and device for actively suppressing pressure oscillations in a hydraulic system
CN103241287A (zh) * 2013-05-07 2013-08-14 常州机电职业技术学院 一种液压转向系统压力调节装置
CN102239076B (zh) * 2008-10-29 2013-10-30 Zf操作系统有限公司 液压动力转向器
WO2017087756A1 (fr) * 2003-01-02 2017-05-26 Trw Automotive U.S. Llc Système de direction à assistance hydraulique

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10118739A1 (de) * 2001-04-17 2002-11-14 Trw Fahrwerksyst Gmbh & Co Verfahren zum Steuern eines Servolenksystems
DE102004020434A1 (de) * 2004-04-27 2005-11-24 Daimlerchrysler Ag Lenkungsvorrichtung für Kraftfahrzeuge
FR2918029B1 (fr) * 2007-06-27 2009-11-20 Renault Sas Circuit hydraulique d'actionnement de direction assistee et vehicule automobile muni de celui-ci.
CN102372025B (zh) * 2010-08-26 2013-06-12 中联重科股份有限公司 电控闭式液压转向系统、控制方法和具有该系统的车辆
CN102336215A (zh) * 2011-08-12 2012-02-01 丹阳市长江汽车部件有限公司 一种汽车起重机动力转向装置
JP6020881B2 (ja) * 2012-04-10 2016-11-02 株式会社ジェイテクト 油圧式パワーステアリング装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4006792A (en) * 1975-10-29 1977-02-08 Zahnradfabrik Friedrichshafen Ag Steering system with auxiliary power assist
US4705132A (en) * 1984-11-12 1987-11-10 Nissan Motor Company, Limited Power steering gear
US4825751A (en) * 1986-09-18 1989-05-02 Bendix France Controlled bypass and flow-control valve unit for hydraulic power steering system
US5135068A (en) * 1989-09-04 1992-08-04 Jidosha Kiki Co., Ltd. Hydraulic reaction device for power steering apparatus
US5758739A (en) * 1993-11-13 1998-06-02 Hydraulik Nord Gmbh Hydraulic steering circuit and steering apparatus
US6415885B2 (en) * 2000-02-14 2002-07-09 Bosch Braking Systems Co., Ltd. Steering damper
US6520278B2 (en) * 1998-07-10 2003-02-18 Showa Corporation Hydraulic power steering device

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1112598A (fr) * 1954-10-16 1956-03-15 Piston d'amortisseur hydraulique à passage d'huile de section variable
DE2838151A1 (de) 1978-09-01 1980-03-13 Bosch Gmbh Robert Lenkung fuer kraftfahrzeuge
US4467884A (en) 1982-07-12 1984-08-28 Robertson Gene V Steering stabilizer
DE4029156A1 (de) 1989-10-09 1991-04-11 Volkswagen Ag Hydraulisch unterstuetztes lenkungssystem
DE19620975B4 (de) * 1996-05-24 2006-08-31 Zf Friedrichshafen Ag Hilfskraftlenkung mit Dämpfungsventilen für Kraftfahrzeuge
DE19651500C1 (de) 1996-12-11 1998-04-09 Daimler Benz Ag Dämpferventilanordnung
DE19842840A1 (de) * 1998-09-18 2000-03-23 Zahnradfabrik Friedrichshafen Dämpfungsventil

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4006792A (en) * 1975-10-29 1977-02-08 Zahnradfabrik Friedrichshafen Ag Steering system with auxiliary power assist
US4705132A (en) * 1984-11-12 1987-11-10 Nissan Motor Company, Limited Power steering gear
US4825751A (en) * 1986-09-18 1989-05-02 Bendix France Controlled bypass and flow-control valve unit for hydraulic power steering system
US5135068A (en) * 1989-09-04 1992-08-04 Jidosha Kiki Co., Ltd. Hydraulic reaction device for power steering apparatus
US5758739A (en) * 1993-11-13 1998-06-02 Hydraulik Nord Gmbh Hydraulic steering circuit and steering apparatus
US6520278B2 (en) * 1998-07-10 2003-02-18 Showa Corporation Hydraulic power steering device
US6415885B2 (en) * 2000-02-14 2002-07-09 Bosch Braking Systems Co., Ltd. Steering damper

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017087756A1 (fr) * 2003-01-02 2017-05-26 Trw Automotive U.S. Llc Système de direction à assistance hydraulique
US7152709B2 (en) * 2003-12-23 2006-12-26 Hyo Chun Co., Ltd. Industrial vehicle
US20050133294A1 (en) * 2003-12-23 2005-06-23 Hyo Chun Co., Ltd. Industrial vehicle
US20050252667A1 (en) * 2004-05-05 2005-11-17 James Berkeley Trap rake steering travel limiter
US7077215B2 (en) * 2004-05-05 2006-07-18 Textron Inc. Trap rake steering travel limiter
US20090173565A1 (en) * 2005-12-19 2009-07-09 Kenneth John Dennis Method and apparatus for enhancing vehicle performance
US7798281B2 (en) 2005-12-19 2010-09-21 Kenneth John Dennis Method and apparatus for enhancing vehicle performance
US20070193641A1 (en) * 2005-12-22 2007-08-23 John Dooley Power steering system frequency suppressor
US7296651B2 (en) * 2005-12-22 2007-11-20 Eaton Corporation Power steering system frequency suppressor
AU2007100088B4 (en) * 2006-02-06 2007-03-08 Truck Whisperer Limited Method and apparatus for enhancing car performance
US20090198411A1 (en) * 2008-02-06 2009-08-06 Kohls Mark T Electronic steering damper systems and vehicles including same
US7970511B2 (en) 2008-02-06 2011-06-28 Honda Motor Company, Ltd. Electronic steering damper systems and vehicles including same
CN102239076B (zh) * 2008-10-29 2013-10-30 Zf操作系统有限公司 液压动力转向器
US20110302976A1 (en) * 2008-12-05 2011-12-15 Georg Keintzel Method and apparatus for semiactive reduction of pressure oscillations in a hydraulic system
US20120000543A1 (en) * 2008-12-05 2012-01-05 Georg Keintzel Method and device for actively suppressing pressure oscillations in a hydraulic system
CN103241287A (zh) * 2013-05-07 2013-08-14 常州机电职业技术学院 一种液压转向系统压力调节装置

Also Published As

Publication number Publication date
US20020148670A1 (en) 2002-10-17
JP3689055B2 (ja) 2005-08-31
EP1234748B1 (fr) 2003-11-12
JP2002308126A (ja) 2002-10-23
EP1234748A1 (fr) 2002-08-28
DE50100952D1 (de) 2003-12-18

Similar Documents

Publication Publication Date Title
US6820714B2 (en) Hydraulically supported steering system
US4687223A (en) Suspension system for vehicle
US5080392A (en) Suspension unit
EP2483574B1 (fr) Amortisseur réglable
EP1477397B1 (fr) Amortisseur de direction de motocycle
US5107970A (en) High pressure sealing system and method
GB2120355A (en) Variable-damping-force shock absorber
EP0416554B1 (fr) Système d'alimentation en liquide comprenant un dispositif d'atténuation des vibrations de pression
WO2003040586A1 (fr) Amortisseur de chocs avec amortissement en fonction de frequence
US20070176392A1 (en) Motorcycle provided with a steering damper
CN107614924B (zh) 减震器
US6138596A (en) Damped steering mechanism for a watercraft
KR100192381B1 (ko) 자동차의 동력조향장치
US6491313B1 (en) Variable damper assembly
KR100314400B1 (ko) 유압 동력 조향 장치
US4940106A (en) Articulated vehicle with hydraulic steering
US4742883A (en) Pinion ball bearings with preload adjustment for power rack and pinion steering gears
US6206421B1 (en) Control cylinder for a steering system of a motor vehicle
JP2002349630A (ja) 摩擦制御油圧緩衝器およびサスペンション制御装置
JP2000506472A (ja) 減衰弁装置
JP2862134B2 (ja) シヨツクアブソーバ
GB2051714A (en) Hydraulic power-assisted steering system for motor vehicles
US6450286B1 (en) Rack and pinion power steering system with variable damping characteristics
US4627637A (en) Damping force-variable damper device for vehicles provided with power steering device
US20080230301A1 (en) Steering System for Motor Vehicles

Legal Events

Date Code Title Description
AS Assignment

Owner name: VISTEON GLOBAL TECHNOLOGIES, INC., MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SCHYMEZYK, ARMIN;SICKERT, DIRK;REEL/FRAME:012971/0607;SIGNING DATES FROM 20020430 TO 20020506

CC Certificate of correction
AS Assignment

Owner name: AUTOMOTIVE COMPONENTS HOLDINGS, LLC, MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:VISTEON GLOBAL TECHNOLOGIES, INC.;REEL/FRAME:016835/0471

Effective date: 20051129

CC Certificate of correction
FPAY Fee payment

Year of fee payment: 4

AS Assignment

Owner name: FORD MOTOR COMPANY, MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:AUTOMOTIVE COMPONENTS HOLDINGS, LLC;REEL/FRAME:021253/0225

Effective date: 20080717

Owner name: FORD MOTOR COMPANY,MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:AUTOMOTIVE COMPONENTS HOLDINGS, LLC;REEL/FRAME:021253/0225

Effective date: 20080717

AS Assignment

Owner name: FORD GLOBAL TECHNOLOGIES, LLC, MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FORD MOTOR COMPANY;REEL/FRAME:022562/0494

Effective date: 20090414

Owner name: FORD GLOBAL TECHNOLOGIES, LLC,MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FORD MOTOR COMPANY;REEL/FRAME:022562/0494

Effective date: 20090414

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Expired due to failure to pay maintenance fee

Effective date: 20121123